A Design Principle for Predicting Flexible Metal-Organic Frameworks

Metal-organic frameworks, MOFs, are porous organic-inorganic hybrid materials that hold the potential for developing newtechnologies to tackle some of the pressing global challenges such as pollution, climate change and energy crisis. Their typical lowmass densities, high internal surface area, large pore volumes and facile chemistry makes them suitable for application in gas storage,filtration, extraction, catalysis and so on. Some MOFs are known to show a substantial degree of structural flexibility wherein theframework reversibly expands/contracts when subjected to external stimuli like pressure/heat/light or during absorption/desorption.This structural flexibility, if fully understood, can be used to enable the technological development of MOF-based recyclable filters,switchable catalysts, threshold sensors, stimulus-induced drug delivery systems with integrated key-lock functionality, compressiblegas tanks and so on. However, the origin of this flexibility has not yet been sufficiently understood to enable the rational design offlexible MOFs. This research project aims to provide a conceptual understanding on the origin of this flexibility at the atomic regimeby analysing all unique building units, topologies, and frameworks of all published MOFs to design a universally robust metric forpredicting flexibility and mechanical properties of MOFs with the overarching goal of providing a theoretical methodology for thecrystal engineering of flexible MOFs.